The function of the Gene Transfer Core is to provide a facility for the construction, screening, large-scale purification, and tittering of replication-defective recombinant adenoviruses. Recombinant adenoviruses provide a reliable method for high efficiency gene transfer into adult cardiocytes and for directly altering the phenotype. Specifically, the core will 1) maintain 293 kidney cells in culture, 2) amplify and maintain purified stocks of the pdeltaE1sp1A shuttle plasmid and the pJM17 adenovirus plasmid, 3) construct recombinant adenoviruses by the homologous recombination procedure in 293 kidney cells, 4) propagate recombinant adenoviruses in 293 cells with large-scale purifications, and 5) titer purified adenoviruses by plaque assays in 293 cells. The core will also be responsible for long-term storage of recombinant adenoviruses and will assist individual investigators in carrying out gene transfer protocols in adult cardiocytes.